Release mechanism

ABSTRACT

A pull-cable-type of release mechanism incorporating a latch and a spring release, whereby the actuating pressure applied to the mechanism can be multiplied many times in terms of thrust or pull directed to a release cable. The release mechanism includes many safety features including a cocking member lock, safety pin incorporation, and other structural advantages inducing an operator to follow a given procedure to insure that load release will occur when desired.

nited States Patent Caufield 1 Jan. 18,1l72

[54] RELEASE MECHANISM 21 Appl. No.: 53,180

[52] 11.8. C1. ..74/2 [51] Int. Cl. ....G05g 17/00 [58] Field of Search..74/2

[56] References Cited UNITED STATES PATENTS 2,256,965 9/1941 Sexton..74/2

53 9 l 48 J 46 l 39 4 47 2,764,027 9/1956 Otto ..74/2 3,279,262 10/1966Olson ..74/2

Primary Examiner--Milton Kaufman Attorney-M. Ralph Shaffer ABSTRACT Apull-cable-type of release mechanism incorporating a latch and a springrelease, whereby the actuating pressure applied to the mechanism can bemultiplied many times in terms of thrust or pull directed to a releasecable. The release mechanism includes many safety features: including acocking member lock, safety pin incorporation, and other structuraladvantages inducing an operator to follow a given procedure to insurethat load release will occur when. desired.

11 Claims, 16 Drawing Figures 4| 49 59 rr 52 1e SHEET 1 UP 4 INVENTOR.EDWARD C. CAUFIELD F I G 3 HIS ATTORNEY alssspss PATENTEBJAMBWZ SHEET 2[1F 4 FIG. 6

FIG. 7

INVENTOR. EDWARD C. CAUFIELD HIS ATTORNEY mmmmewz 3.635096 SHEET 3 [1F 4FIG. I3

IDIVENTOR. EDWARD c. CAUFI LD BY W HIS ATTORNEY PATENTED JAM 8 I972SHEET u 0F 4 EDWARD C. CAUFIELD FIG. I6

HIS ATTORNEY FIG. l5

RELEASE lVmCIIANISM The present invention relates to release mechanismsand, more particularly, to a new and improved release mechanism of thecable-thrust type wherein a latchable operating spring is utilized tosupply a positive thrust to the actuating cable of the mechanism, whichthrust can be translated to conventional operating mechanisms of releasehooks, bomb shackle assemblies, and so forth.

Many types of mechanisms, such as a helicopter bondrelease mechanism,require the pull or thrust of a release cable to effect a releasefunction. Many of such devices are dependent for actuation upon thenature or condition of the pull of the cable. It would of course bedesirable to have a very large cable thrust present regardless of thenature or magnitude of the pressure applied to an operating lever orother means to accomplish cable thrust. Present devices are also unsafein many contexts in that a procedure is not imposed upon the user tomake sure that his cable release mechanism is operating effectivelyprior to helicopter takeoff, by way of example.

Accordingly, a principal object of the present invention is to provide anew and improved release mechanism.

An additional object is to provide a new and improved release mechanismof the cable-pull type.

An additional object is to provide a release mechanism which isconstructed for connection or coupling to various types of releasemechanisms such as helicopter load release hooks, bomb shackles, and soforth, all of which rely upon a cable-pull to effect a hook, pin, orother type release.

A further object of the invention is to provide a new and irnprovedrelease mechanism for helicopters which will be suitable for preflightcheck out in a manner such as to insure and give the pilot confidencethat a load can be released while the pilot is in flight.

A further object of the present invention is to provide a safety pinfeature as a safety mechanism for a release mechanism, such safety pinbeing locked in the release mechanism at desired times.

A further object is to provide a release mechanism which relies for itseffectiveness upon the latching and release of an actuating spring, thespring being utilized to effect a rapid thrust or pull upon the controlcable of the mechanism.

A further object of the invention is to provide a release mechanismdesigned to preclude inadvertent actuation thereof either throughinadvertent lever movement or through vibration forces translated to themechanism during flight or otherwise.

The features of the present invention which are believed to be novel areset forth with particularity in the appended claims. The presentinvention, both as to its organization and manner of operation, togetherwith further objects and advantages thereof, may best be understood byreference to the following description, taken in connection with theaccompanying drawings in which:

FIG. I is a side elevation of release mechanism incorporating thefeatures of the present invention.

FIG. 2 is a plan view of the structure shown in FIG. 1.

FIG. 3 is a horizontal section taken along the line 3-3 in FIG. I, thelever portion of the release mechanism being shown in fragmentary view.

FIG. 4 is an enlarged sectional detail and is taken along the line 4-4in FIG. ll.

FIG. 5 is an enlarged fragmentary sectional detail and is taken alongthe line S5 in FIG. I.

FIGS. 6 and 7 are side elevations, principally in sectional view,illustrating the release mechanism as being in loaded and firedconditions, respectively.

FIG. 8 is a side elevation of the release mechanism in its loadedcondition.

FIG. 9 is similar to FIG. 8, illustrating the safety pin as having beenpulled and the lever actuated to effect a cable pull upon the controlcable of the device.

FIG. 10 is similar to FIG. 9 but illustrates the release mechanism beingactuated to recock the same for subsequent use.

FIG. I1 is similar to FIG. l0, illustrating the condition of theequipment once recocking has been completed.

FIG. 12 illustrates a side elevation of the release mechanism of theinvention wherein the trigger or lever of the device is inadvertentlydepressed while the safety pin remains installed, the constructionfunctioning to raise slightly the cocking member so to release its lockrelative to the housing of the device.

FIG. 13 illustrates a further manipulation of the release mechanism,relative to FIG. 12, so that a repositioning of the lever or trigger iseffected prior to recocking the mechanism.

FIG. I4 is an exploded view of the entire apparatus of the releasemechanism.

FIG. 15 illustrates use of the release mechanism in a helicoptercontext.

FIG. 16 is an enlarged fragmentary sectional view illustrating inschematic form the manner in which the lower end of the control cableassociated with the release mechanism can be connected to theconventional operating mechanism of a load hook so that the cable willeffect at desired times a release of such load hook.

The release mechanism of the present invention is generally shown inFIGS. I-3 and is identified as mechanism I0. The same is shown toinclude a housing II which is preferably cast from a light weight metalmaterial such. as aluminum. Housing 11 is provided with a compositerelease pin boss I2 accommodating release pin I3. The latter is of theball-check type, of standard design, wherein a depression of button I4of the release pin permits balls I5 to be withdrawn inwardly of the pinso as to permit the ejection of release pin I3 in the direction of arrowA. A lever or release trigger 16 is provided and is pivoted to andwithin the housing I I by means of pivot pin 17 pressed in the housing.Housing ll includes a base mounting flange I8 which is provided withsuitable bores 19, for example, to provide for the mounting of theflange l8, and hence of housing II, to appropriate structure 20 such asa floor. The latter will be provided with a relief aperture, as at 2I,to accommodate a depending boss 22.

In returning for a moment to the mounting flange 18, it is to beobserved that while two mounting bolt sets 23 with their respectiveapertures 19 have been shown, it will be understood that two, three ormore apertures 19 may be provided for accommodating a correspondingnumber of attachments.

FIGS. 6 and 7 illustrate the interior of the housing structure when thesame assumes a ready-to-fire and also a fired" condition, respectively.As seen in FIG. 7 by way of example, the lower boss 22 is threaded at 23to interiorly receive a threaded fitting 24. The same may be providedwith interior threads 25 to accommodate a locking nut 26. The lockingnut retains in place the flanged end of the outer flexible sheath 28 offlexible cable structure 29. The cable structure includes the flexiblecable member 30 which at its uppermost end M is pressed into aperture 32of shaft 33. Shaft 33 will generally be made of metal and be providedwith a shoulder 34 serving as a limit stop relative to shaft 33 inconnection with upstanding boss 35. The boss 35 is integral with housingII, and the interior thereof as at 36 accommodates the reciprocatingmovement of enlarged cylindrical portion 37 of shaft 33.

FIG. 7 illustrates the condition of the structure wherein the same hasbeen fired or unlatched so as to accommodate a lift ing of shaft 33 and,hence, of enlarged portion 37 to the upper portion of chamber C asformed by interior bore 36. A bore 38 operates to journal or otherwisepermit passage of the shaft 33 through the upstanding boss 35.

Shaft 33 includes a shoulder 39 and an upper portion 40 of reducedcross-sectional dimension. Pressed onto portion 40 is a washer 41. Thepurpose for the inclusion of washer M is to serve as a bearing andthrust agent when the shaft 33 is lowered, upon the user rotating thecocking member 42 in a manner hereinafter explained. It is noted that anylon bearing member or washer 43 is provided as bearing means in theconstruction.

As to cocking member 42 itself, the same includes knurled cylindricalhandle portion 44 and also a depending central structure 45 which isappropriately exteriorly threaded at 46. These enlarged threadscooperate with the threads 47 of an interior threaded sleeve 48.Threaded sleeve 48, during assembly, is pressed upwardly, relative tothe drawing of FIG. 7, into the interior of a stainless steel sleeve 49,by way of example, such that shoulders 50 and 51 of these two partsabut. The compression spring 52 engages at its upper end 53 the surface54 so as to keep shoulders 50 and 51 in intimate contact.

Nylon bushing 55 is disposed over the shaft 33 in the manner illustratedand is retained in place by washer 56 and nut 57. The latter may beprovided with a cotter key 58 which is disposed through alignedapertures of the nut 57 and reduced portion 40 of shaft 33 in the mannershown in FIG. 7.

As to lever or trigger 16, which can be a foot-lever, the same is alsoillustrated in FIG. 7 as being pivoted about pivot pin 17, previouslyshown in FIG. 1. Lever 16 includes an upper portion 59 forming a latch60. Latch 60 selectively engages a circumferential slot 61 formed in theside of the steel sleeve 49. Where the wall thickness of the steelsleeve is a very small dimension, then the slotted area can include arecessed portion 62 in the threaded sleeve 45.

Housing 11 includes a relief recess 63 for accommodating the positioningof compression spring 64. The latter coacts as between the housing at 65and a thrust button 66 incorporating a central stub-shaft portion 67.

Threaded into opposite sides of housing 11 at threaded bores 69 are apair of limit-stop bolts or screws 70. See FIG. 1 wherein arepresentative one of the diametrically opposed screws is illustrated.These screws include blunt ends at 71 which selectively engage surface72 (see FIG. 14) of vertical slot 73. These vertical slots 73, see FIG.14, are disposed on opposite sides of the steel sleeve 49. A safety pinreceiving slot 74 is provided in the left-hand slot configuration at 73in FIG. 14 to accommodate the safety insertion of release pin 13 whenthe same is installed in the manner shown in FIG. I. When the pin isremoved, the steel sleeve 49 is free to move upwardly against thepressure of spring 52 when a lever 16 is depressed.

The release mechanism of the present invention operates as follows.Consider that the same is installed in a helicopter as shown in FIG. 15.In such event the cable assembly 29 proceeds downwardly to theconventional cargo-hook 76, installed in FIG. as a secondary cargo hook.The usual control 77 proceeds to a primary cargo-hook 78, and the latterloops through a looped end 79 of cable 80 which supports, via its endstrands or end loops 81 and the load 82. The employment of primary andsecondary cargo hooks is standard to the art, and their installations aswell are standard, except of course for the release mechanism 10comprising the present invention. See by way of example cable-pullactuated, load release hook models 2A ISE illustrated at the third andfourth pages of the E. R. C. (Eastern Rotocraft Corporation) currentstandard manual (undated).

FIG. 16 illustrates the manner in which the cable assembly 29 can beattached to a representative one of the cargo hooks. In particular, FIG.16 illustrates that the interior flexible cable may be provided with aball-end fitting at 83, with extreme pressure being applied to the ballto squeeze against and thus rigidly secure the cable 30 thereto. Ball 83will be positioned in the operating mechanism 84 of the release hook 85e.g., 76, 78), more particularly disclosed in the referenced abovecited, such that when the cable is pulled upwardly, a release of thehook takes place. More particularly, the ball and applicants assembliesmerely by way of example. The specific manner of connecting the pull,"i.e., cable 30, to the operating mechanism, whatever standard mechanismis employed, forms no part of the present invention. The presentinvention comprises an operative release mechanism incorporating acontrol cable which, upon actuation of the mechanism as through a leveror other means, rapidly thrustingly pulls such cable.

The operating sequence of the release mechanism of the present inventionis illustrated in FIGS. 8-13.

FIG. 8 illustrates the mechanism 10 as assuming its loaded condition. Atthis point, and provided the operator has previously pulled out therelease pin 13 as shown in FIG. 9, then depression or actuation of lever16 will trip the mechanism so as to enable the spring 52 to thrustupwardly the cocking member 42 and the cable 30 as well. Again, this isaccomplished by virtue of the fact that the shaft 33 affixed to thecable in fact keyed for motion to the member 42 as shown in FIG. 7.

To recock the mechanism the user merely rotates in a clockwise directionthe cocking member 42 so that rotation of the same will automaticallycompress spring 52. Where righthand threads are used instead ofleft-hand threads as shown, then the cocking operation will assume areverse rotation to that illustrated.

FIG. 11 illustrates that once the cocking member 42 has been returned toits original position, the safety release pin 13 may be returned to itsposition shown in FIG. 11 and also in FIG. 1.

FIG. 4 illustrates that once the cocking mechanism 42 is so returned inthe manner shown in FIG. 11 then the pin 87 will engage a detent recess88 in member 42. Pin 87 may form the composite pin structure, as at 89,having a pressed washer 90 pressed to the shaft 91 of the pin. A spring92 is provided to' back the pin and a spring guide or casing 93 may beincluded. The pin combination is inserted in recess bore 94 and the sameretained in place by a locking nut 95. See FIG. 4 in connection withthis construction. Thus, a complete return of the cocking member 42 willaccomplish the detent of FIG. 4 so as to retain the cocking memberagainst movement during vibration periods; hence, the cocking member 42is locked in place.

Suppose at this juncture even though the pin is installed as shown inFIG. 12, the lever is actuated accidentally. Such actuation as shown inFIG. 12 will produce an upward movement of cocking member 42 so thata"release as between pin 87 and aperture 88 exists. Kindly note thespacing between the housing 11 and cooking member 42 in FIG. 12.However, at this juncture the pin 13 will not be capable of beingwithdrawn. This is because of the upward pressure of the lower surfaceof the side slot 74 of steel sleeve 49 as well as the presence of thesupplied balls for the safety pin 13. Now since the pin is not withdrawnor withdrawable, this forces the user to check his system. He does thisby rotating upwardly the cocking member 42 so as to draw upwardly on thecable and thus actuate and thereby test his load hook. When the upperextremity of the cable has been reached, then the continued rotationwill drive the steel sleeve 49 downwardly so that slot 61 ultimatelycomes in engagement with the latch or hook portion 60 of lever 16. Atthis point the lever will spring upwardly and be ready for use when thecocking member 42 is returned to its downward position. It is to benoted that, as seen in FIG. 13, when the cocking member is at itsuppermost position after the operation immediately described above hastaken place, the pin can be removed. However, since the cable is up, areverse rotation of cocking member 42 is necessary to return the cableto its lowermost position preparatory for lever depression.

In the event that the operator has inadvertently depressed the leverwith his foot at the time the cocking member 42 is in its uppermostposition, the lever will be displaced slightly downwardly in the mannershown in FIG. 12. To recock, all that is needed is for the user torotate, perhaps a quarter-tum, the cocking mechanism so as to thrust thesteel sleeve down and thereby permit the latch of the lever to reengagethe slot of the steel sleeve. At that time the pin can be removed, oreven be left in place while the cocking member is rotated downwardly tothe position shown in FIG. 6.

So that the reader may fully comprehend the significance of thisinvention, it should be emphasized that the design of the releasemechanism of the invention requires the user to check out his systemcompletely so that he knows that when airbom he will be able to releasehis load. Furthermore, it is most important to note that most cablerelease systems will operate on an exertion of say 5 to pounds ofpressure. The present invention may be designed so as to utilize a 70 or80 pound spring, so that when the release function is performed, aguaranteed, positive,- high-power thrust is applied to the releasecable.

When the user is on the ground, again, and is preparing to board hishelicopter, he should indeed know that his release mechanism and hisprimary system are operating satisfactorily so that he is completelyassured the load can be released when airborn. Thus, it isnt a questionof merely pulling the pin and then stepping on the lever to release theload. Rather, the user must be assured that the mechanism is operatingsatisfactorily and must be forced to go through the previously describedprocedure such that such assurance is justified. For example, if heenters the helicopter and the mechanism is ready for firing, in anyevent he can simply pull the safety pin and then depress the lever withhis hand or foot so as to uncock or release the mechanism. On the otherhand, if someone has inadvertently depressed the lever prematurely whilethe pin was installed, then the user cannot now pull the pin but ratherwill follow the procedure outlined in connection with F168. 12 and 113,and the discussion appertaining thereto, so that the lever is properlypositioned. In either event, the user will know that upon actuation onthe ground, his system is in good order and also that a positive cablethrust can be achieved and will later be realized upon depression of thelever.

After such has been positively determined, he will return with his handthe cocking mechanism to its downward position and replace the pin sothat he is ready to operate the same once aloft. Qt course the user maywish simply to leave the pin out as he is ascending in flight ready toperform his desired service.

It should be further emphasized that the spring 52should be chosen to beof sufficient strength such that not only will a positive strong pull beachieved upon release of the mechanism, but also the safety pin will beretained in place and not be capable of being pulled out in the eventthat the operating lever is prematurely depressed.

While particular embodiments of the present invention have been shownand described, it will be obvious to those skilled in the art thatchanges and modifications may be made without departing from thisinvention in its broader aspects, and, therefore, the aim in theappended claims is to cover all such changes and modifications as fallwithin the true spirit and scope of this invention.

lclajm:

l. A release mechanism including, in combination, a housing, firststructural means movably disposed in said housing for carrying aflexible cable, a cable secured to said first structural means andextending beyond said housing, sleeve means slideably disposed in saidhousing, a compression spring operably disposed within said housingbetween said housing and said sleeve means, manually rotatable meansthreadedly engaging said sleeve means for depressing said firststructural means to compress said spring and cock said sleeve means and,subsequently, for extending said first structural means and said cablein one direction, means for releasably latching said sleeve means whensaid spring is compressed, and ac tuatable means for unlatching thesame, for thrusting said first structural means and said cable in apredetermined direction, reverse to that of said one direction, underthe pressure of said spring 2. he mechanism of claim I wherein saidsleeve means comprises a sleeve disposed for reciprocal movement withinsaid housing, axially, interiorly threaded means carried by said sleevemeans and operatively, reactively engaging said spring and threadedlyengaging said depressing means, said means for depressing said firststructural means comprising a cocking member provided with a shaftsecured to said cable and having an inner, depending threaded portionthreadedly engaging said threaded means, said sleeve means and saidhousing in cluding means providing a limit stop to limit the outerextension of said first structural means relative to said housing underthe pressure of said spring.

3. The mechanism of claim 2 wherein said sleeve includes a latchingslot, said latching means including a latching portion constructed forreleasable engagement with said latching slot.

4. The mechanism of claim 2 wherein said actuatable means comprises alever pivoted to said housing and having said latching means.

5. A mechanism according to claim 2. wherein said cocking memberincludes an upper access aperture constructed to provide access forretentive engagement for retention means secured to said shaft, saidshaft being so provided with retention engagement means.

6. The mechanism of claim 2 wherein, when said cocking member isthreaded downwardly, said cocking member and said housing are providedwith releasably engageable detent means for releasably locking saidcocking member with respect to said housing when said cocking member isreturned to a position towards said housing to compress said spring.

7. The mechanism of claim 6 wherein said housing includes a withdrawablesafety pin means releasably engaging as a stop abutment means of saidsleeve means when said cocking member is threaded downwardly toreleasably engage said detent means, said housing, sleeve, safety pinmeans, and said actuatable means being constructed and arranged suchthat depression of said actuatable means is sufficient to release saidcocking member from said housing even when said safety pin means ininstalled in place in said housing.

8. A mechanism according to claim ll wherein said housing includes adepending threaded boss, said cable being provided with a flexiblesheath, and means for securing said flexible sheath to said boss suchthat said cable proceeds upwardly therethrough.

9. The mechanism of claim 1 wherein said housing is provided withaperture means for receiving a safety pin, said mechanism being providedwith a safety pin releasably engageable with said aperture means, saidsleeve means being constructed and arranged to provide stop meansengaging said pin when the latter is installed in said housing at saidaperture means to prevent full length outer movement of said firststructural means should inadvertent movement of said latching meansunlatch said first structural means with respect thereto.

10. A mechanism according to claim 1 wherein said actuatable means isspring-biased upwardlly with respect to said housing.

ill. The mechanism of claim 1 wherein said depression means rotatablyand retentively engages said first structural means.

1. A release mechanism including, in combination, a housing, firststructural means movably disposed in said housing for carrying aflexible cable, a cable secured to said first structural means andextending beyond said housing, sleeve means slideably disposed in saidhousing, a compression spring operably disposed within said housingbetween said housing and said sleeve means, manually rotatable meansthreadedly engaging said sleeve means for depressing said firststructural means to compress said spring and cock said sleeve means and,subsequently, for extending said first structural means and said cablein one direction, means for releasably latching said sleeve means whensaid spring is compressed, and actuatable means for unlatching the same,for thrusting said first structural means and said cable in apredetermined direction, reverse to that of said one direction, underthe pressure of said spring.
 2. The mechanism of claim 1 wherein saidsleeve means comprises a sleeve disposed for reciprocal movement withinsaid housing, axially, interiorly threaded means carried by said sleevemeans and operatively, reactively engaging said spring and threadedlyengaging said depressing means, said means for depressing said firststructural means comprising a cocking member provided with a shaftsecured to said cable and having an inner, depending threaded portionthreadedly engaging said threaded means, said sleeve means and saidhousing including means providing a limit stop to limit the outerextension of said first structural means relative to said housing underthe pressure of said spring.
 3. The mechanism of claim 2 wherein saidsleeve includes a latching slot, said latching means including alatching portion constructed for releasable engagement with saidlatching slot.
 4. The mechanism of claim 2 wherein said actuatable meanscomprises a lever pivoted to said housing and having said latchingmeans.
 5. A mechanism according to claim 2 wherein said cocking memberincludes an upper access aperture constructed to provide access forretentive engagement for retention means secured to said shaft, saidshaft being so provided with retention engagement means.
 6. Themechanism of claim 2 wherein, when said cocking member is threadeddownwardly, said cocking member and said housing are provided withreleasably engageable detent means for releasably locking said cockingmember with respect to said housing when said cocking member is returnedto a position towards said housing to compress said spring.
 7. Themechanism of claim 6 wherein said housing includes a withdrawable safetypin means releasably engaging as a stop abutment means of said sleevemeans when said cocking member is threaded downwardly to releasablyengage said detent means, said housing, sleeve, safety pin means, andsaid actuatable means being constructed and arranged such thatdepression of said actuatable means is sufficient to release saidcocking member from said housing even when said safety pin means ininstalled in place in said housing.
 8. A mechanism according to claim 1wherein said housing includes a depending threadEd boss, said cablebeing provided with a flexible sheath, and means for securing saidflexible sheath to said boss such that said cable proceeds upwardlytherethrough.
 9. The mechanism of claim 1 wherein said housing isprovided with aperture means for receiving a safety pin, said mechanismbeing provided with a safety pin releasably engageable with saidaperture means, said sleeve means being constructed and arranged toprovide stop means engaging said pin when the latter is installed insaid housing at said aperture means to prevent full length outermovement of said first structural means should inadvertent movement ofsaid latching means unlatch said first structural means with respectthereto.
 10. A mechanism according to claim 1 wherein said actuatablemeans is spring-biased upwardly with respect to said housing.
 11. Themechanism of claim 1 wherein said depression means rotatably andretentively engages said first structural means.